JPH09280695A - Plate type condenser for absorption freezer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a heat transmission coefficient and hence halve the size of a condenser for making an apparatus compact in a condenser where refrigerant vapor is cooled to obtain a refrigerant fluid by constructing the condenser with two perpendicular corrugated plates having uneven part vertically and upper and lower parts and opposite ends thereof closed. SOLUTION: This plate type condenser 21 is constructed by disposing two corrugated plates 22a, 22b such that projecting parts of the plates and recessed parts of the same are opposed, closing upper and lower parts 28, 29 and opposite side parts 23a, 23b, and forming a cooling water outlet head 24 at a position near the one side part 23a a cooling water inlet head 25 at a position near the other side part 23. For the condenser 21 a plurality of them are disposed up and down parallelly to the flow direction of the refrigerant vapor, i.e., vertically. With such a condenser 21 the condensed refrigerant fluid easily flows down and is separated at the lowermost part from the condenser 21 so that a refrigerant liquid film on a refrigerant outer surface becoming heat transfer resistance is made thin and hence a a heat transmission coefficient.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a plate type condenser used in an absorption refrigerator.

[0002]

2. Description of the Related Art FIG. 1 is a system diagram for explaining the principle of an absorption refrigerator 1. In the regenerator 2, the rare absorbing liquid 3 is heated by a heating source such as city gas, and the refrigerant vapor is separated to obtain a concentrated absorbing liquid. The refrigerant vapor is cooled and condensed in the condenser 4 to become the refrigerant liquid 5. The refrigerant liquid 5 is depressurized by the pressure reducing valve 6, cools the liquid to be cooled, for example, water, by the evaporator 7, and the refrigerant liquid itself evaporates. The refrigerant vapor is absorbed by the regenerator 2 in the absorber 8 in order to keep the evaporator 7 at a reduced pressure and accelerate the evaporation of the refrigerant liquid.
It is absorbed by the concentrated absorbent from. The concentrated absorption liquid absorbs the refrigerant vapor to become the diluted absorption liquid 9, is pressurized by the solution pump 10, and is sent to the regenerator 2 via the heat exchanger 11. The concentrated absorption liquid 3 from the regenerator 2 is decompressed by the pressure reducing valve, and the heat exchanger 1
1 to the absorber 8. Since it is necessary to discharge heat to the outside when the absorbing liquid absorbs the refrigerant vapor and when the refrigerant vapor condenses, the cooling water flows from the absorber 8 to the condenser 4. The evaporator 7 is provided with a refrigerant pump 11, and the unevaporated refrigerant liquid 12 is circulated.

A typical condenser of the prior art is provided with a horizontal multi-tube cooling water pipe, the refrigerant vapor descends from the upper side to the lower side of the cooling water pipe to cool the refrigerant vapor, and the outer surface of the cooling water pipe. It becomes a refrigerant liquid by being condensed at. In order to improve the condensation efficiency of the condenser, it is necessary to increase the heat transfer area and promptly separate the refrigerant liquid from the outer surface of the cooling water pipe. In a horizontal multi-tube condenser, the condensed refrigerant liquid comes to drip on the cooling water pipe arranged below, and when the heat transfer area is increased, the number of cooling water pipes increases and the number of stages increases.
The refrigerant liquid must be removed from the cooling water pipe many times, and the condensation efficiency decreases. Further, there is a problem that the number of cooling water pipes increases and the condenser cannot be made compact.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a compact plate type condenser having a high condensation efficiency for use in an absorption refrigerator.

[0005]

According to the present invention, a regenerator for separating a refrigerant vapor from a dilute absorption liquid to obtain a concentrated absorption liquid, a condenser for cooling the refrigerant vapor to obtain a refrigerant liquid, and a refrigerant liquid are provided. Evaporating under reduced pressure, including an evaporator that cools the liquid to be cooled, and an absorber that absorbs the refrigerant vapor generated in the evaporator with a concentrated absorbing liquid,
In an absorption refrigerator in which an absorption liquid is circulated between a regenerator and an absorber via a heat exchanger, two vertical corrugated plates having vertical unevenness and having upper and lower parts and both side parts closed The cooling water is supplied from one side and discharged from the other side into the inside sandwiched between the two corrugated plates, which is constituted by It is a plate type condenser. According to the present invention, a plate type condenser having two corrugated plates having vertical corrugations and having closed upper and lower portions and both side portions is used, and the plate is parallel to the flow direction of the refrigerant vapor. Since it can be arranged vertically, the condensed refrigerant liquid easily flows down, and only needs to be separated from the condenser once at the bottom. For this reason, the thickness of the refrigerant liquid film on the outer surface of the condenser, which becomes the heat transfer resistance, becomes thin, and the heat transmission coefficient can be improved. Further, the plate interval (distance between adjacent plate type condensers) can be narrowed to about 14 mm required for piping, and the heat transfer area can be increased by 20 to 30% in the same area as compared with a flat plate having the same length and width. With these, the size can be reduced to about 1/2 of that of the conventional condenser of the horizontal multi-tube type.

Further, the present invention is characterized in that the two corrugated plates are combined so that the concave portions and the convex portions face each other, and the core material is arranged in the cooling water passage. According to the present invention, the two corrugated plates face each other with the concave portion and the convex portion facing each other, and the core material is arranged inside, so that turbulent flow can be caused in the flow of the cooling water to improve the heat transfer performance. it can. The core material also acts as a reinforcing material, and has a large pressure difference between the inner and outer surfaces of the condenser (for example, outer surface 0.1 atm, inner surface 6-8 atm).
Endure.

Further, in the present invention, the corrugated plate has a pitch of 2 to 5.
mm, wave depth 0.5-2 mm, bending radius of convex part 0.2
It is characterized in that it is ˜2 mm. In accordance with the invention, the preferred shape of the corrugated sheet is shown.
This shape is obtained as a result of experiments by the present inventors, and it is possible to keep the condensation efficiency high and to easily process it. The material of the condenser is not particularly limited in the present invention, but is preferably made of metal having high thermal conductivity, and is also preferably made of copper as in the case of the horizontal multi-tube cooling pipe from the viewpoint of processing.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described more specifically by way of embodiments. The structure of the absorption refrigerator is the same as that described in the related art with reference to FIG.

FIG. 2 is a front view of the plate type condenser 21 of the present invention, and FIG. 3 is a plan view. Two corrugated plates 22a, 22b
Are provided so that the concave portions and the convex portions face each other, and the upper and lower portions 28 and 29 and both side portions 23a and 23b are closed. A cooling water outlet header 24 is formed near one side portion 23a, and a cooling water inlet header 25 is formed near the other side portion 23b. The cooling water that has cooled the absorber 8 is supplied from the cooling water supply pipe 26 to the cooling water inlet header 25.
Then, it is traversed between the two corrugated plates 22a and 22b from right to left, for example, and is guided from the cooling water outlet header 24 to the cooling water discharge pipe 27.

A plurality of condensers 21 are arranged in the vertical direction in FIG. 3, and are provided in parallel to the direction in which the refrigerant vapor flows indicated by the arrow 31 in FIG. 2, that is, vertically. In the case of the double effect, the size of the condenser 21 is, for example, width A = 665 mm and length B = 125 mm, and one sheet is used as a 1 RT (refrigeration ton) condenser. Therefore, for a 100 RT absorption refrigerator, 100 condensers 21 are arranged in the vertical direction in FIG.

FIG. 4 is a sectional view showing the shape of a corrugated plate used in the condenser 21 of the present invention. Two corrugated plates 22a, 22b
The cooling water traverses the inner surface of the plate from the top to the bottom of FIG. 4, for example. The condensed refrigerant liquid flows down perpendicularly to the paper surface of FIG. 4, and flows from the lower portion 29 (see FIG. 2) of the condenser 21 to the refrigerant liquid reservoir 5
To be dropped. Experiments were carried out on corrugated plates of various shapes to maximize the condensation efficiency, and the pitch P of corrugated plates was 2 to 5 mm,
Preferably 3-4 mm, wave depth h = 0.5-2 mm,
Preferably, it is 0.7 to 1.5 mm, and the mountain portion bending radius r = 0.
2 to 2 mm, preferably 1.0 mm was obtained.

As shown in FIG. 4, a core material 35 is provided in the left-right direction in the cooling water passage, and a baffle plate 36 is provided at a portion where the recesses face each other. The baffle plate 36 restricts the lateral flow of the cooling water. 5 is a cross-sectional view taken along the section line VV of FIG. The heartwood 35 is
The portions of the corrugated plates 22a and 22b where the convex portions face each other are bent in a corrugated cardboard shape to maintain the shape of the corrugated plates 22a and 22b and restrict the flow of the cooling water in the width direction. The flow of the cooling water is restricted by the core material 35 and the baffle plate 36 and becomes a turbulent flow to increase the heat transfer efficiency.

Further, the absorber of the present invention can be designed to have one sheet per 1RT or one sheet per 2RT, and the cost can be reduced by mass production.

[0014]

As described above, according to the present invention, the size of the condenser of the absorption refrigerator can be reduced to about half, and the size of the absorption refrigerator can be greatly reduced.

[Brief description of drawings]

FIG. 1 is a system diagram for explaining the principle of an absorption refrigerator 1.

FIG. 2 is a front view of a condenser 21 for an absorption refrigerator according to an embodiment of the present invention.

FIG. 3 is a plan view of the condenser 21.

4 is an enlarged cross-sectional view showing a relationship among corrugated plates 22a and 22b of the condenser 21, a core material 35, and a baffle plate 36. FIG.

5 is a cross-sectional view taken along the section line VV of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Absorption refrigerator 2 Regenerator 4 Condenser 7 Evaporator 8 Absorber 21 Plate-type condenser 22 of one embodiment of the present invention 22 Corrugated plate 23 Side part 26 Cooling water supply pipe 27 Cooling water discharge pipe 35 Heartwood 36 Baffle plate

Claims (3)

[Claims] 1. A regenerator that separates a refrigerant vapor from a dilute absorbent to obtain a concentrated absorbent, a condenser that cools the refrigerant vapor to obtain a refrigerant liquid, and a refrigerant liquid that is evaporated under reduced pressure to be cooled. Absorption type that includes an evaporator that cools the liquid and an absorber that absorbs the refrigerant vapor generated in the evaporator with a concentrated absorbing liquid, and circulates the absorbing liquid between the regenerator and the absorber via a heat exchanger. In a refrigerator, it has vertical corrugations, is composed of two vertical corrugated plates that are closed at the top and bottom and on both sides, is placed in the refrigerant vapor, and is placed inside the two corrugated plates. A plate type condenser for an absorption refrigerator, wherein cooling water is supplied from one side and discharged from the other side. 2. The absorption refrigerator according to claim 1, wherein the two corrugated plates are combined so that the concave portions and the convex portions face each other, and the core material is arranged in the cooling water passage. Plate condenser for. 3. The absorption according to claim 1, wherein the corrugated plate has a pitch of 2 to 5 mm, a wave depth of 0.5 to 2 mm, and a bending radius of a convex portion of 0.2 to 2 mm. Plate condenser for rotary refrigerator.